Effect of maturity and processing on bitter compounds in Thai tangerine juice

Optimum conditions of fruit maturity and processing for improved quality of Thai tangerine fruit juice were evaluated. Limonin and naringin components causing bitterness, acidity, total soluble solids and vitamin C were quantified in specified fruit setting and processing conditions.
Higher limonin contents were observed in tangerine fruits harvested early in the season of 1989, whereas naringin contents gradually decreased with maturity. The optimum harvesting time for Thai tangerine fruit which meets the worldwide quality indicators of extracted juice was nine months after fruit set.
Low temperature storage of tangerine juice was only effective in delaying limonin formation if not pasteurized, which resulted in higher limonin concentrations at the start of the storage period. However, naringin concentrations of tangerine juice were not affected by storage conditions and the pasteurization process. Lower extraction pressure of juice resulted in low limonin and naringin concentrations.     

Prediction of titratable acidity, malic acid, and citric acid in bayberry fruit by near-infrared spectroscopy

An experiment was conducted to simultaneously measure titratable acidity, malic acid, and citric acid of bayberry fruit in a nondestructive manner using near-infrared (NIR) transmittance spectroscopy and chemometrics. The sampling set included different cultivars that were obtainable from different areas in China. Calibration models using partial least squares (PLS) regression were developed based on GB 12293-90 of China and with high-performance liquid chromatography (HPLC) as reference methods. Different preprocessing methods and different wave bands were applied. The correlation coefficient of calibration (r_c), root-mean-square error of calibration (RMSEC), and root-mean-square error of prediction (RMSEP) of the best model for titratable acidity was 0.8959, 2.24, and 2.89 g/L, respectively, with the range of 10,000-5405 cm⁻¹. R_c, RMSEC, and RMSEP values for malic acid and citric acid were 0.6689, 0.32, 0.47 and 0.8970, 1.51, 2.12 g/L, respectively. The prediction accuracies could not be improved by using first and second derivative pretreatment methods. Due to the short time consumption and low monitoring cost, NIR spectroscopic technique has its potential for the rapid and nondestructive prediction of titratable acidity and citric acid in bayberry fruit in a temperature-controlled room, although the accuracy was not high.     

Yield and quality of juice from passion fruit (Passiflora edulis), maypops (P incarnata) and tetraploid passion fruit hybrids (P edulis × P incarnata)

Yield and properties of juice from purple and yellow passion fruit (Passiflora edulis), maypops (P incarnata) and tetraploid hybrids of P edulis and P incarnata were compared. Weight, proportion filled, number of seeds and yield of juice per fruit were lower in tetraploid hybrids than in P edulis. Acidity and soluble solids were highest in tetraploid hybrids and lowest in maypops. Fructose, glucose, sucrose, citric and malic acids were present in all samples. Fructose and glucose were the major sugars in passion fruit; sucrose was highest in tetraploid hybrids and maypops. Citric, the predominant acid in all samples, was highest in the yellow passion fruit followed by tetraploid hybrids and purple passion fruit. Malic acid was highest in purple-flowered maypop and lowest in white-flowered maypop.     

采收时间对核桃青皮成分和功能活性的影响

目的探究采收期对新鲜核桃青皮的化学成分、抗氧化和抗菌特性的影响。方法以不同采收成熟度(1P:2017.8.20、2P:2017.8.26、3P:2017.9.1)的"香铃"核桃为实验材料,手工脱除新鲜的核桃青皮,通过测定不同采收成熟度所得青皮中的胡桃醌、总酚、黄酮、水解单宁的含量,抗氧化和抗菌活性,以探讨采收期对新鲜核桃青皮的影响。结果随着采收成熟度的增加,核桃青皮中的抗氧化活性呈现上升趋势;总酚和水解单宁的含量先上升后趋于平稳。其中,第二成熟度(2P)采收的核桃青皮中,胡桃醌和黄酮的含量最高,分别为0.58 mg/g FW、2.67 mg/g FW。所有成熟度所得核桃青皮水提物,对革兰氏阳性菌有不同程度的抑制。第三成熟度(3P)所得核桃青皮水提物对枯草芽孢杆菌的抑菌圈直径达到了1.35 cm。结论第二、三成熟度采收的核桃青皮,含有丰富的活性成分,且具有良好的抗氧化和抗菌活性。     

Effects of harvesting procedure,storage time and climatic conditions on cooking time of lentils (Lens culinaris Medikus)

In an experiment conducted over 2 years in Larissa, the effects on the cooking times of six lentil varieties of different harvest periods (early and late), seed storage for 1 year and climatic conditions prevailing during seed production were studied. Cooking time was estimated by measuring seed hardness using a penetrometer (PNR‐6). Late harvesting (when the plants were completely dry) increased cooking times by 6–16% in comparison with early harvesting (when the plants were partly green). This increase was less for the short‐cooking genotypes ‘Dimitra’, ‘Samos’ and ‘Thessalia’ than for the long‐cooking genotypes ‘Arachova’ and ‘Nikaia’. After 1 year of seed storage, cooking times increased on average by 6–9%. Seeds produced during a dry year (1995) required on average 38% less time to cook than seeds produced during a wet year (1996), irrespective of harvest period or duration of seed storage. © 2001 Society of Chemical Industry     

Effect of enzymatic macerate treatment on rutin content, antioxidant activity, yield, and physical properties of asparagus juice

ABSTRACT:  Asparagus is a vegetable with high antioxidant activity. In this research, asparagus juice was produced from fresh asparagus macerate treated with a carbohydrases mixture (Viscozyme) at 37 °C for up to 8 h. Rutin content, antioxidant activity, yield, soluble solid content, and color of the produced asparagus juice were determined. The results showed that Viscozyme significantly increased the yield of asparagus juice, especially in the 1st hour, which was higher than control (without Viscozyme treatment), but the juice had significantly less rutin content than control and had higher antioxidant activity than control only in the 1st 2 h. Juice with Viscozyme treatment had significantly higher soluble solid content than control. The greenness of asparagus juice deteriorates quickly for both the Viscozyme group and control. Viscozyme had advantage in producing juice with high yield, antioxidant activity, and soluble solid content in shorter time (2 h) of treatment compared to control.     

Effects of exogenous nitric oxide on contents of soluble sugars and related enzyme activities in 'Feicheng' peach fruit

BACKGROUND: Sugar content is one of the main characteristics related to the quality of fruit. Research confirms that nitric oxide (NO) involves a physiological process and prolongs the storage life of fruit. However, little attention has been paid to the effects of NO on sugar metabolism in fruit during storage. In this study, the effect of different concentrations (0, 10, 30 µmol L^?1) of exogenous NO treatment on sugar content and related enzyme activities in ‘Feicheng’ peach fruit was investigated during storage (0–12 days after harvest) at room temperature (25 °C). RESULTS: Results showed that the decrease of firmness and accumulation of sugar and acid:sugar ratio in peach fruit during storage were significantly inhibited by treatment with 10 µmol L^?1 NO. Treatment with 10 µmol L^?1 NO could promote fructose and glucose metabolism during the first 4 days of storage, and increase the content of sucrose and the activities of sorbitol dehydrogenase, sorbitol oxidase and sucrose phosphate synthase in peach fruit during storage. However, acid invertase activity from 8 to 12 days of storage and neutral invertase activity during the first 4 days of storage were inhibited by treatment with 10 µmol L^?1 NO. At the same time, treatment with 10 µmol L^?1 NO inhibited sucrose synthase (SS) activity in decomposition during storage and SS activity in synthesis from 8 to 12 days of storage. CONCLUSION: Treatment with 10 µmol L^?1 NO had a significant impact on content of soluble sugars and related enzyme activities in ‘Feicheng’ peach fruit during storage (0–12 days) at room temperature (25 °C). Copyright © 2011 Society of Chemical Industry     

甘蔗混合汁粒径分布及陶瓷微滤膜过滤阻力研究

建立了甘蔗混合汁中颗粒粒径分布测定和分析方法;研究了0．1μm、0．2μm和0．45μm陶瓷微滤膜分析甘蔗混合汁时的阻力分布,探讨了不同膜元件主要阻力形式,确定了阻力分析方法。结果表明：致密性膜的制造精度越高,过滤料液时总阻力相对较小,孔隙率高的膜元件堵塞阻力随膜孔径减小而降低,利于膜通量的恢复和延长使用时间。     

Effect of foliar sprays containing calcium,magnesium and titanium on peach (Prunus persica L) fruit quality

Sprays containing Ca²⁺, Mg²⁺ or Ti⁴⁺ were applied to peach trees in several combinations. Effects of treatments on the commercial quality of fruits, especially focused on improving their mechanical properties, are discussed. All treatments containing titanium increased tree performance (branch elongation, flowering and fruit set intensities) and fruit size. At harvest, fruits from Ti‐treated trees showed improved resistance to compression and penetration, as well as a decrease in weight loss during postharvest storage. A similar response was obtained for external colour, though all treatments seemed to delay somewhat the apparent ripening status. Nevertheless, fruits from Ti‐treated trees showed better behaviour in the evolution of colour parameters during storage than did control fruits. Titanium application showed significant increases in iron, copper and zinc concentrations in the peel and calcium concentration in the peel and flesh. This improvement in calcium absorption is explained as a consequence of the beneficial effect of titanium on the absorption, translocation and assimilation processes. Copyright © 2004 Society of Chemical Industry     

Effect of thermal and non‐thermal pasteurisation on the microbial inactivation and phenolic degradation in fruit juice: a mini‐review

Fruit juice has been traditionally preserved by thermal pasteurisation. However, the applied heat can cause detrimental effects on health‐promoting components such as phenolic compounds. Several non‐thermal technologies such as membrane filtration, pulsed electric field (PEF) and ultraviolet (UV) exposure are promising methods developed for liquid food preservation. In particular, the combination of UV and PEF has proven to be more effective for microbial inactivation and maintaining nutritional quality of fruit juice compared with individual applications. © 2012 Society of Chemical Industry     

Effect of cold storage and ozone treatment on physicochemical parameters,soluble sugars and organic acids in Actinidia deliciosa

The production of kiwi fruits is a dynamic agricultural activity in Corsica (France). The fruits are either consumed directly or used to produce kiwi wine. They are often stored for 4–6 months in industrial freezer chambers at 0 °C or industrial ozone chambers. The aim of this study was to measure physical, chemical and fungicidal parameters, soluble sugars and non-volatile organic acids during storage in each of these types of chamber. Various standard and instrumental methods (physicochemical techniques, HPLC) in conjunction with statistical analysis were used. During storage, the kiwi mass, firmness and acidity decreased, whereas reducing sugar, °Brix and pH increased. There were statistical differences between the two chambers regarding reducing sugar and acidity. The ozone gas treatment had a fungicidal effect on Botrytis cinerea. The major soluble sugar present in the kiwi fruit was fructose, followed by glucose and sucrose. The concentrations of these sugars increased during storage in both air at 0 °C and ozone-enriched air. Organic acids are one of the important factors influencing fruit flavour. Citric and quinic acids predominated over malic, tartaric and ascorbic acids. During storage in the ozone chamber, concentrations of non-volatile organic acids decreased sharply after 25 weeks. Storage at 0 °C enabled better retention of organic acids.     

Effect of solid feed level and types of roughage on passage kinetics of milk replacer,concentrate, and roughage in veal calves

This study aimed (1) to provide estimates of total mean retention times of milk replacer (MR), concentrates, and roughage in veal calves fed a mixed diet; (2) to determine the effect of level and type of solid feed (SF) on passage kinetics of MR, concentrates, and roughages in veal calves; and (3) to compare passage kinetics in veal calves using the fecal excretion curves of indigestible markers and a noninvasive ¹³C tracer breath test approach to determine whether the latter technique can serve as an alternative. At the start of the trial, 48 Holstein-Friesian calves (6 wk of age; 68 ± 7.7 kg of body weight; BW) were assigned to 1 of 4 dietary treatments (for statistical analysis, only 39 calf observations were used). Three treatments contained chopped wheat straw as roughage in the SF mixture in a concentrate:roughage ratio of 90:10 (dry matter basis). The SF level was 20 g/kg of metabolic BW per day (low straw), 30 g/kg of metabolic BW per day (middle straw), or 40 g/kg of metabolic BW per day (high straw). The fourth treatment (high hay) contained long perennial ryegrass hay as roughage in the SF mixture in a concentrate:roughage ratio of 70:30 (dry matter basis, at 40 g/kg of metabolic BW per day). The quantity of MR was fixed for the high straw treatment, whereas the amount of MR for the other treatments during the adaptation period was adjusted based on a pair gain strategy (i.e., exchanging ration components but keeping similar net energy). At the end of the adaptation period, calves ranged from 12 to 15 wk of age with an average BW of 123 ± 8.6 kg. Passage kinetics of concentrates were estimated by measuring ¹³C enrichment excess of CO₂ in breath from a pulsed-dose of [1-¹³C]octanoate. Passage kinetics of roughage, concentrates, and MR were also estimated using fecal excretion curves obtained after ingestion of chromium-mordanted roughage, Yb₂O₃, and Co-EDTA, respectively. We conclude that [1-¹³C]octanoate cannot serve as a measure for oro-duodenal transit of concentrates because of unrealistic estimates. Based on the fecal excretion curves, we concluded that the total mean retention time of MR (i.e., time to peak; the moment that the excretion curve reaches peak concentration) was, on average, 12.4 h, and that the passage kinetics of MR was not affected by the level or type of SF. The mean retention time of concentrates was shorter (21.4 h) than that of both straw (59.1 h) and hay (36.8 h), and was not affected by the level or type of SF. Also, the mean retention time of the slowest compartment (i.e., the rumen) was shorter for concentrates (39.6 h) than that of straw (110.0 h) and hay (59.2 h). Contrary, the passage of roughage was affected by level and type of SF. Long hay increased time to peak by 22.3 h and decreased ruminal mean retention time by 50.8 h relative to chopped straw, indicating that the passage rate of long hay is faster than that of chopped straw. We conclude that the level and type of SF only affects the passage kinetics of roughage and not that of MR and concentrates.     

Effect of increasing manganese concentration in nutrient solution on the antioxidant activity,vitamin C,lycopene and polyphenol contents of tomato fruit

ABSTRACT

This study evaluated the effect of increasing manganese (Mn) nutrition on the content of antioxidative compounds such as vitamin C, lycopene and polyphenols, and the antioxidant activity of tomato (Lycopersicon esculentum Mill., cvs ‘Alboney F1’ and ‘Emotion F₁’) fruit. Plants were grown in rockwool using a nutrient solution with the following content of Mn (mg dm^–3): 0.0, 0.3, 0.6, 1.2, 2.4, 4.8, 9.6 and 19.2. The level of vitamin C and lycopene decreased with the increasing Mn nutrition. Since the colour of fruits was correlated with the change in carotenoid content, the decrease in lycopene content promoted the reduction of redness and increase of yellowness of fruits. However, total polyphenol content and antioxidant activity significantly increased when plant were exposed to toxic levels of Mn. Observed changes could be the result of the oxidative stress induced by high concentrations of Mn. Polyphenolic compounds play a crucial role in the plant’s response to Mn stress and affect predominantly the total antioxidant properties of fruits, which could be used as a source of phenolics. Moreover, total phenolic content measurement, as an easy and inexpensive method, could be used as an indicator of Mn-induced stress in fruits of tomato.     

Short communication: Effect of washing method,grinding size,and the determination of an indigestible fraction on in situ degradation of starch in mature corn grain

The objectives of this study were to determine (1) the effect of grinding size (1, 2, 4, and 6 mm) to determine effective ruminal disappearance (ERD); (2) the most adequate method to estimate the rapidly degradable fraction (A); (3) a time point to measure the indigestible fraction (C); and (4) the viability of using fewer time points to estimate starch fractional disappearance rate (k_d) of mature corn grain. Fraction A was determined by rinsing in a bucket or washing machine, rumen immersion followed by bucket or washing machine, and water immersion for 30 min followed by bucket or washing machine. Ruminal in situ incubations were performed at 48, 72, 96, and 120 h to determine fraction C, and at 0 (washing machine), 3, 6, 12, 18, 24, and 48 h to determine the kinetics of starch disappearance. Models were used with either 2 or 3 pools and k_d was determined by the linear slope of the log-transformed bag residues as a proportion of incubated samples over time. The ERD was calculated as A + B [k_d/(k_d + kp)], where kp is the ruminal fractional passage rate = 16.0% h^?1. Data were analyzed using PROC MIXED of SAS (SAS Institute Inc., Cary, NC) with the fixed effects of run (for fraction A analysis only) method (either washing or model), grinding size, and method by grinding size interaction, with cow as a random effect. Correlation between estimates calculated using all time points or combinations of 2 and 3 time points were determined using PROC CORR. Fraction A was reduced as grinding size increased, but was not altered by washing method. Samples ground at 6 mm had greater fraction C than other grinding sizes at 48, 72, or 96 h, but not at 120 h. Model affected the slowly degradable fraction (B) values solely, but the difference was minor (0.5 percentage units). Greater fractions B and C but reduced k_d and ERD were observed as grinding size increased. Based on correlation analysis the 2-pool model, incubation times of 0, 3, and 48 h were suitable to evaluate ruminal starch degradation kinetics in mature corn. Ruminal in situ incubation at 120 h highlighted the lack of a fraction C of starch (0.13% of starch). Washing method did not affect determination of fraction A of starch. Ruminal in situ incubations of 0, 3, and 48 h for starch degradation kinetics using a 2-pool model were adequate for mature ground corn, but 120 h of incubation is suggested to confirm the existence or absence of a fraction C. Grinding size affected starch degradation kinetics and fraction A determination.     

Effect of yeast supplementation on performance,rumination time,and rumen pH of dairy cows in commercial farm environments

The aims of the present study were to evaluate the effects of live yeast supplementation (Vistacell MUCL 39855, AB Vista, Marlborough, UK) on performance, rumination time, and rumen pH on dairy cows in commercial farm environments. Three trials were carried out, the trials lasted 12 (trial 1), 15 (trial 2), and 19 wk (trial 3). In each trial, 14 multiparous Holstein dairy cows were allocated to 2 groups that received (trial 1) a standard diet plus yeast, (trial 2) an acidogenic diet plus yeast, and (trial 3) grazing pasture plus yeast. Milk production, milk chemical characteristics, body weight and body condition score, rumination time, and rumen pH were monitored for each group throughout the 3 trials. No statistically significant differences were observed in any of the 3 trials for any of the recorded variables. In contrast, an effect of time (period or days in milk) on rumen pH was observed in all 3 of the trials, as time spent under the acidotic thresholds increased across the experimental periods; however the differences were not associated with live yeast supplementation. No effect of live yeast supplementation was observed in any of the 3 trials reported. Further research should include studies on animals at different stages of lactation (with emphasis on transition period and early lactation), consuming more challenging diets (higher level of inclusion of concentrates or starch), or under different environments such as grazing of succulent forages. Such studies might be required to elucidate any possible effect of live yeast supplementation of dairy cows when the rumen environment is under challenge.     

Effects of washing procedure,particle size and dilution on the distribution between non‐washable,insoluble washable and soluble washable fractions in concentrate ingredients

The effects of washing procedure, particle size and dilution on the distribution of non‐washable (NWF), insoluble washable (ISWF) and soluble washable (SWF) fractions were studied. The effects of three washing procedures (Yang (Y), Melin (M) and in situ (IS)) on the size of NWF, ISWF and SWF in six concentrate ingredients (maize, barley, milo, peas, lupins and faba beans), ground at two different particle sizes, were compared. Method M was further developed (method SM) by reducing the dilution ratio; its effect on NWF, ISWF and SWF was compared. A new washing method was developed (method AA) which involved continuous washing of nylon bags in a centrifuge beaker; its effect on NWF, ISWF and SWF at different dilutions with water was compared with the IS, M, SM and Y methods. The effects of different dilutions on SWF and soluble true protein (STP) in six concentrate ingredients were studied. The effects of grain, washing method and particle size on the size of NWF and ISWF were significant, with significant interactions between grain and particle size, grain and washing method, particle size and washing method, but no interaction between grain type, washing method and particle size. In method Y the size of NWF was smaller than in the other methods. The results showed that, except in lupins, NWF in grains was significantly higher than in legume seeds. Increasing the particle size significantly increased NWF, whereas ISWF was decreased. The size of SWF in legume seeds was higher than in the grains. Increasing the dilution, increased STP in legume seeds, but not in grains. Copyright © 2007 Society of Chemical Industry     

Influence of origin,harvesting time and weather conditions on content of inositols and methylinositols in sea buckthorn (Hippophaë rhamnoides) berries

Inositols and methylinositols play an important role in human physiology. Inositols and methylinositols in berries of three subspecies of sea buckthorn (Hippophaë rhamnoides) were analysed using gas chromatography combined with a flame ionisation detector and mass spectrometry. The wild Chinese berries (H. rhamnoides ssp. sinensis) contained higher levels of l-quebrachitol (1l-2-O-methyl-chiro-inositol) and methyl-myo-inositol (average 615 and 58 mg/100 ml juice, respectively) than the Finnish (H. rhamnoides ssp. rhamnoides, 276 and 11 mg/100 ml juice, respectively) and the Russian (H. rhamnoides ssp. mongolica, 228 and 16 mg/100 ml juice, respectively) berries (P < 0.001). The content of myo-inositol was higher in the Chinese and the Russian berries than in the Finnish berries (26 and 20 mg/100 ml juice vs. 8 mg/100 ml juice, P < 0.001). In the Chinese berries, the contents of methyl-myo-inositol and l-quebrachitol increased, whereas that of myo-inositol decreased from late September to late November. The content of the l-quebrachitol in the Chinese berries correlated negatively with the air temperature and the number of frost-free days, suggesting a possible role of the compound in the cold resistance of sea buckthorn.